No abstract available.
Phosphatidylcholines* ; Phospholipases A2* ; Phospholipases*

No abstract available.
Macrophages* ; Phospholipases A2* ; Phospholipases* ; Tumor Necrosis Factor-alpha*

No abstract available.
Animals ; Glucose* ; Mesangial Cells* ; Phospholipases A2* ; Phospholipases* ; Rats*

This study investigated the effects of the methanol extracts of Morinda citrifolia containing numerous anthraquinone and iridoid on phospholipase A2 (PLA2) isozyme. PLA2 activity was measured using various PLA2 substrates, including 10-pyrene phosphatidylcholine, 1-palmitoyl-2-[14C]arachidonyl phosphatidylcholine ([14C]AA-PC), and [3H]arachidonic acid (AA). The methanol extracts suppressed melittin-induced [3H]AA release in a concentration-dependent manner in RAW 264.7 cells, and inhibited cPLA2/sPLA2-induced hydrolysis of [14C]AA-PC in a concentration- and time-dependent manner. A Dixon plot showed that the inhibition by methanol extracts on cPLA2 and sPLA2 appeared to be competitive with inhibition constants (Ki ) of 3.7microgram/ml and 12.6microgram/ml, respectively. These data suggest that methanol extracts of Morinda citrifolia inhibits both Ca2+-dependent PLA2 such as, cPLA2 and sPLA2. Therefore, Morinda citrifolia may possess anti-inflammatory activity secondary to Ca2+-dependent PLA2 inhibition.
Arachidonic Acid ; Cytosol ; Hydrolysis ; Methanol ; Morinda ; Phosphatidylcholines ; Phospholipases ; Phospholipases A2

BACKGROUND: According to the notion of the immunoregulatory functions of moxifloxacin (MFX), the effect of MFX on the neutrophilic respiratory burst in conjunction with the expression of cytosolic phospholipase A2 (cPLA2) was investigated. METHODS: The effects and possible mechanisms of MFX on neutrophilic respiratory burst in oleic acid (OA)-induced acutely injured rats lung and OA-stimulated, isolated murine neutrophils were probed, associated with the expression of cytosolic phospholipase A2 in vivo and in vitro. RESULTS: In the OA-induced acutely-injured lungs, neutrophils were accumulated, which was attenuated by MFX. The parameters denoting a neutrophilic respiratory burst, such as nitro blue tetrazolium reaction, cytochrome-c reduction, neutrophil aggregation, H2O2 production in neutrophils revealed increased neutrophilic respiratory burst by OA, and MFX decreased all of these parameters. In addition, the enhanced expression of cPLA2 in the lung and isolated murine neutrophils by OA were decreased by MFX. CONCLUSION: MFX suppresses the OA-induced neutrophilic respiratory burst by the suppression of cPLA2 in neutrophils.
Animals ; Aza Compounds ; Cytosol ; Lung ; Neutrophils ; Oleic Acid ; Phospholipases ; Phospholipases A2 ; Phospholipases A2, Cytosolic ; Quinolines ; Rats ; Respiratory Burst

Animals ; Cardiovascular System ; chemistry ; Female ; Group II Phospholipases A2 ; blood ; Group IV Phospholipases A2 ; blood ; Group V Phospholipases A2 ; blood ; Group X Phospholipases A2 ; blood ; Male ; RNA, Messenger ; genetics ; Rats ; Rats, Wistar

Human secreted phospholipase A2 GIIE (hGIIE) is involved in inflammation and lipid metabolism due to its ability of hydrolyzing phospholipids. To reveal the mechanism of substrate head-group selectivity, we analyzed the effect of mutation of hGIIE on its activity and selectivity. hGIIE structural analysis showed that E54 might be related to its substrate head-group selectivity. According to the sequence alignment, E54 was mutated to alanine, phenylalanine, and lysine. Mutated genes were cloned and expressed in Pichia pastoris X33, and the enzymes with mutations were purified with 90% purity by ion exchange and molecular size exclusion chromatography. The enzymatic activities were determined by isothermal microthermal titration method. The Km of mutant E54K towards 1,2-dihexyl phosphate glycerol decreased by 0.39-fold compared with that of wild type hGIIE (WT), and the Km of E54F towards 1,2-dihexanoyl-sn-glycero-3-phosphocholine increased by 1.93-fold than that of WT. The affinity of mutant proteins with phospholipid substrate was significantly changed, indicating that E54 plays an important role in the substrate head-group selectivity of hGIIE.
Humans ; Kinetics ; Mutation ; Phospholipases A2, Secretory ; Phospholipids ; Saccharomycetales ; Substrate Specificity

STUDY DESIGN: Evaluation of phospholipase A2 production according to cell type of human intervertebral disc. SUMMARY OF LITERATURE REVIEW: It was reported that the phospholipase A2 activity in human lumbar disc herniation was more active than that in other tissues. OBJECTIVES: The purpose of this study was to evaluate the differences between the cells of anulus fibrosus and nucleus pulposus when lactate was added to the culture medium. MATERIALS AND METHODS: Cells from the anulus fibrosus and nucleus pulposus of a human intervertebral disc were prepared enzymatically. After the monolayer was set up, the cells were divided to three groups and lactate doses of a 0mM, 2mM or 5mM were added respectively. At two week after lactate addition the production of phospholipase A2 was measured by Northern blotting. RESULTS: Cells of nucleus pulposus produced a small amount of phospholipase A2. Those of anulus fibrosus showed a high activity of phospholipase A2 production. The concentration of lactate did not influenced on the production of phospholipase A2. CONCLUSION: The anulus fibrosus has an important role in the production of phospholipase A2 and is thought to be related with generation of discogenic pain.
Blotting, Northern ; Cell Culture Techniques ; Humans* ; Intervertebral Disc* ; Lactic Acid ; Phospholipases A2* ; Phospholipases*

OBJECTIVES: A limited retrospective study of patients with rheumatoid arthritis (RA) found that serum phospholipase A2 (PLA2) activity correlates with disease activity. To assess the strength of this relationship we investigated prospectively 25 patients with RA using a double blind approach. METHODS: Twenty five patients who fulfilled the 1987 American College of Rheumatology criteria for RA had clinical and laboratory assessments. PLA2 activity was measured before and after treatment of 3 months in patients with RA. Fourteen healthy individuals were also enrolled as controls. PLA2 activity was assayed using E.coli membrane phospholipid substrate labelled with[14C]-oleic acid. RESULTS: 1) Serum PLA2 activity was significantly higher in patients with RA than that of normal healthy controls (p<0.001). 2) In Patients with RA, synovial fluid PLA2 activity was higher than serum PLA2 activity, and a positive correlation between PLA2 in synovial fluids and matched sera was found in these patients (p<0.05). 3) After treatment, PLA2 activity was significantly decreased with improvement of clinical(morning stiffness and Ritchie index) and laboratory(ESR, CRP and rheumatoid factor)assessments (p<0.001). 4) Among the clinical and laboratory markers of disease activity, ESR showed the best correlation with serum PLA2 activity (r=0.493, p<0.05). 5) In the patients who did not respond clinically to treatment (n=5), there was no significant decrease in PLA2 activity. CONCLUSION: PLA2 activity significantly correlates with RA activity and may serve as an index of disease activity in RA.
Arthritis, Rheumatoid* ; Biomarkers ; Humans ; Membranes ; Phospholipases A2* ; Phospholipases* ; Prospective Studies ; Rheumatology ; Synovial Fluid

OBJECTIVESTo explore the clinical application of anti-human seminal plasma phospholipase A2 (PLA2) monoclonal antibody (McAb) for male infertility.

METHODSEnzyme-linked immunoabsorbent assay (ELISA), immunocytochemistry(ICC), as well as flow cytometry (FCM) analysis were established using two strains anti-human seminal plasma PLA2 McAb prepared by our laboratory to detect the PLA2 content in human seminal plasma and the anterior head region of spermatozoa, respectively. Then the PLA2 content in male infertile patients were compared with that in normal control with fertility. The seminal routine analysis was performed by computer-assisted semen analysis (CASA).

RESULTSThe PLA2 content of infertile groups were (31.13 +/- 14.49) ng/ml in azoospermic patients, (17.71 +/- 12.45) ng/ml in oligospermic patients and (16.46 +/- 11.31) ng/ml in patients with normal sperm density, which were all higher than that of normal controls [(8.09 +/- 3.15) ng/ml, P < 0.01]; There was significantly negative correlation between PLA2 content in seminal plasma and sperm density(r = -0.602, P < 0.05), while there was insignificant correlation between PLA2 and sperm motility or percentage of motility. The PLA2 content in the anterior head region of spermatozoon of male infertile groups was significantly lower than that of normal controls by ICC and FCM(P < 0.01).

CONCLUSIONSPLA2 in human seminal plasma is closely related to male fertility, and the PLA2 deficiency in the head of spermatozoa may be one of the reasons causing male infertility. The methods detecting PLA2 content in seminal plasma and the head of spermatozoa can provide powerful evidences for exploring the mechanism of male infertility.

Adult ; Humans ; Infertility, Male ; enzymology ; Male ; Phospholipases A ; analysis ; Phospholipases A2 ; Semen ; enzymology